module Beaker::Options::HostsFileParser

A set of functions to parse hosts files

Constants

PERMITTED_YAML_CLASSES

Public Class Methods

fix_roles_array(host_options) click to toggle source

Make sure the roles array is present for all hosts

# File lib/beaker/options/hosts_file_parser.rb, line 82
def self.fix_roles_array(host_options)
  host_options['HOSTS'].each_key do |host|
    host_options['HOSTS'][host]['roles'] ||= []
  end
  host_options = host_options.merge(host_options.delete('CONFIG')) if host_options.has_key?('CONFIG')
  host_options
end
merge_hosts_yaml(host_options, error_message) { || ... } click to toggle source

Merges YAML read in the passed block into given OptionsHash

@param [OptionsHash] host_options Host information hash @param [String] error_message Message to print if {::Psych::SyntaxError}

is raised during block execution

@return [OptionsHash] Updated host_options with host info merged

# File lib/beaker/options/hosts_file_parser.rb, line 96
def self.merge_hosts_yaml(host_options, error_message)
  begin
    loaded_host_options = yield
  rescue Psych::SyntaxError => e
    error_message << e.to_s
    raise ArgumentError, error_message
  end

  host_options.merge(loaded_host_options)
end
new_host_options() click to toggle source

Convenience method to create new OptionsHashes with a HOSTS section

@return [OptionsHash] Hash with HOSTS section

# File lib/beaker/options/hosts_file_parser.rb, line 74
def self.new_host_options
  host_options = Beaker::Options::OptionsHash.new
  host_options['HOSTS'] ||= {}
  host_options
end
parse_hosts_file(hosts_file_path = nil) click to toggle source

Read the contents of the hosts.cfg into an OptionsHash, merge the ‘CONFIG’ section into the OptionsHash, return OptionsHash @param [String] hosts_file_path The path to the hosts file

@example

hosts_hash = HostsFileParser.parse_hosts_file('sample.cfg')
hosts_hash == {:HOSTS=>{:"pe-ubuntu-lucid"=>{:roles=>["agent", "dashboard", "database", "master"], ... }

@return [OptionsHash] The contents of the hosts file as an OptionsHash @raise [ArgumentError] Raises if hosts_file_path is not a valid YAML file @raise [Errno::ENOENT] File not found error: hosts_file doesn’t exist

# File lib/beaker/options/hosts_file_parser.rb, line 35
def self.parse_hosts_file(hosts_file_path = nil)
  require 'erb'

  host_options = new_host_options
  return host_options unless hosts_file_path

  error_message = "#{hosts_file_path} is not a valid YAML file\n\t"
  host_options = self.merge_hosts_yaml(host_options, error_message) do
    hosts_file_path = File.expand_path(hosts_file_path)

    raise "#{hosts_file_path} is not a valid path" unless File.exist?(hosts_file_path)

    process_yaml(File.read(hosts_file_path), binding)
  end
  fix_roles_array(host_options)
end
parse_hosts_string(hosts_def_yaml = nil) click to toggle source

Read the contents of a host definition as a string into an OptionsHash

@param [String] hosts_def_yaml YAML hosts definition

@return [OptionsHash] Contents of the hosts file as an OptionsHash @raise [ArgumentError] If hosts_def_yaml is not a valid YAML string

# File lib/beaker/options/hosts_file_parser.rb, line 58
def self.parse_hosts_string(hosts_def_yaml = nil)
  require 'erb'

  host_options = new_host_options
  return host_options unless hosts_def_yaml

  error_message = "#{hosts_def_yaml}\nis not a valid YAML string\n\t"
  host_options = self.merge_hosts_yaml(host_options, error_message) do
    process_yaml(hosts_def_yaml, binding)
  end
  fix_roles_array(host_options)
end
process_yaml(template, b) click to toggle source

A helper to parse the YAML file and apply ERB templating

@param [String] path Path to the file to read @param [Binding] b The binding to pass to ERB rendering @api private

# File lib/beaker/options/hosts_file_parser.rb, line 112
def self.process_yaml(template, b)
  erb_obj = ERB.new(template, trim_mode: '-')
  YAML.safe_load(erb_obj.result(b), permitted_classes: PERMITTED_YAML_CLASSES, aliases: true)
end